Here, in The Netherlands, I've got VDSL2 via the old buried
telephone cable. It's underground all the way, until it enters
our basement and I have not encountered any interference. The
telephone center, where the DSLAM is placed, is some 600 m cable
away and I can get the maximum 52 Mbit/s where the cable enters.
The downstream is divided into 3 frequency blocks. One includes
the 160 m band, the second the 40 m band and the third 20 m.
When I start transmitting in one of these bands, the system
creates a notch in the downstream for that particular band. I
have noted that, after a morning ragchew on 40 m, the notch has
stayed for some 20 minutes, but when I have made short tests in
other bands, the notch disappeared almost immediately.
I don't know if this performance requirement is limited to
Europe. Recently the regulations over here have been sharpened
up for LAN over powerline, requiring notching for ham bands and
some other frequencies.
73,
Kjell, PB3SM - SM6CPI
> -----Original Message-----
> From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of
> Christopher Brown
> Sent: 22 April 2014 10:28
> To: rfi@contesting.com
> Subject: Re: [RFI] VDSL (very-high-bit-rate digital subscriber
line)
>
>
> I am still waiting on getting the house connection refit for
dual pair
> VDSL2 but I have packed the spec-an and a few radios to work.
>
> From what I can tell the situation is not much different than
> ADSL/ADSL2, there are generally alot more issues with RF
> getting into the DSL than the other way around.
>
> I have found plenty of "DSL" noise sources... Switching
> power supplies, and digital noise from the modems
> themselves...conducted common mode noise over cabling/etc...
>
> I have never seen RF interferance from the DSL signal itself
> unless the cable pairs were so poor/impalanced/other than
> they were barely functional for DSL (cable pairs that made a
> better antenna than signal carrier).
>
> The DSL signals are comparatively and depend on the twisted
> pair copper acting as a transmission line. All the same
> stuff that would tend to make them /leak/ would tend to cause
> terrible performance issues with the service as well.
>
>
> On 4/19/14, 9:35 AM, Dale J. via RFI wrote:
> > Anybody have VDSL service to their home? I did a quick
> lookup and it
> > uses copper to the home at frequency band 25 Khz to 25 Mhz.
> My next
> > door just signed up for it. I wonder if that will be my
next
> > challenge.
> >
> > Dale, k9vuj _______________________________________________
RFI
> > mailing list RFI@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rfi
> >
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